The Importance of Patch Testing in Drug Reaction with Eosinophilia and Systemic Symptoms: 10 Years After

• Autor(a) principal: Morgado, Francisca Jácome
• Data de Publicação: 2020
• Outros Autores: Santiago, Luís, Gonçalo, Margarida
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: https://doi.org/10.29021/spdv.78.1.1161
• topic: Drug Hypersensitivity/diagnosis; Eosinophilia/diagnosis; Exanthema/diagnosis; Patch Tests; Eosinofilia/diagnóstico; Exanthema/diagnóstico; Hipersensibilidade a Fármacos/diagnóstico; Testes Epicutâneos

Introduction: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe cutaneous adverse drug reaction. According on the culprit drug(s), imputability can be confirmed by patch test (PT). Our objective was to evaluate the value of PT in DRESS in the last 10 years, in comparison with our study in the preceding 10 years. Material & Methods: From 2009 to 2018, patients with DRESS performed PT at the Dermatology Department of Coimbra University Hospital, with the main culprit drug(s) and all drugs administered concomitantly or suspected of inducing DRESS flares. Drugs at 1% - 10% pet (Chemotechnique diagnostics®) or from a commercial preparation diluted at 10% pet were patch tested. Results: We studied 41 patients (20 male/ 21 female, mean age 53 years). The main culprits were allopurinol (n=15), antiepileptics (n=14), trimethoprim/ sulfamethoxazole (n=4), salazopyrine (n=3), diclofenac (n=2), antiretrovirals, ezetimibe/simvastatin and strontium ranelate (1 each). In 15 patients other drugs (n=18) were suspected of worsening DRESS, amoxicillin (n=8), ciprofloxacin (n=2), cefoxitin (n=2), levofloxacin, ceftriaxone, ceftazidime, vancomycin, acyclovir and metamizole (1 each). A positive PT to the culprit drug was observed in 10 patients (24.3%), all to antiepileptics. All patients tested for alopurinol had negative results. Positive reactions were observed to drugs related with flares in 12/18 suspected drugs (67%), but not to quinolones. Conclusion: Results were similar to the study conducted 10 years before when 18/56 (32.1%) patients had positive PT, mostly to carbamazepine and other anticonvulsants. Distinct from our previous study, when no tests were performed with the antibiotic series or other drugs used after the initiation of DRESS, we showed that PT can be a valuable tool to diagnose co-sensitisation in DRESS and emphasise the importance of testing all medications taken during the whole episode, even when PT has no value for the main culprit, like allopurinol. Recognising a co-sensitisation can prevent a new DRESS induced by the second drug.